1. Field of the Invention
The present invention relates to industrial instruments and machine tools. Particularly, the present invention relates to an industrial instrument and machine tool including a manual pulse generator.
2. Description of the Background Art
Machine tools including a manual pulse generator are conventionally known. In such a machine tool, a manual pulse generator is employed for position control of an object that is the interest of control such as a movable body.
For example, Japanese Patent Laying-Open No. 2007-160449 discloses a machine tool including a manual pulse generator employed in position control. The operation unit of the manual pulse generator includes a feed rod changing switch for selecting which of the feeding direction in the X axis, Y axis, and Z axis the spindle mechanism (tool) and the work attachment mechanism (work) are to be moved relatively, a magnification switch for switching the amount of travel per pulse, and a rotary handle provided rotatably about an axis perpendicular to the front face of the main body, generating a pulse signal according to the rotation amount by rotating about the axis.
There is also known a conventional machine tool rotating the spindle about the rotation axis of the spindle up to a position according to the number of pulse signals generated based on the rotation of the manual pulse generator, i.e. a machine tool having a position control function based on rotation.
There is also known a conventional machine tool including a rotational speed selector switch, a normal rotation button, and a reverse rotation button on an operation panel. In such a machine tool, the user can cause rotation of a spindle that does not have a position control function based on rotation by means of rotational speed control, using the rotational speed selector switch, the normal rotation button, and the reverse rotation button. Specifically, subsequent to determining the speed through the selector switch, the user depresses the normal rotation button or reverse rotation button to cause the spindle to start rotating. The spindle continues rotation in the direction of the depressed button at the determined speed as long as the user is depressing the normal rotation button or reverse rotation button. When the user takes his/her hand off the normal rotation button or reverse rotation button, the spindle stops its rotation.